


What kind of rivalry (what kind of revelry)

by redroseinsanity



Series: Meet me in the grey area [3]
Category: Haikyuu!!
Genre: Alternate Universe - Superheroes/Superpowers, Enemies to Lovers, M/M, Slow Burn, hanamatsu being lil shits, hero! iwaizumi, just me being indulgent, matsuhana - Freeform, villain! oikawa
Language: English
Status: Completed
Published: 2020-06-07
Updated: 2020-06-07
Packaged: 2021-03-04 06:49:11
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,373
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24569542
Author URL: https://archiveofourown.org/users/redroseinsanity/pseuds/redroseinsanity
Summary: Heroes and villains never do some things. They don't think dream about each other, they don't have brunch because their best friends happen to be dating and they certainly don't catch feelings.Iwaizumi and Oikawa happen to do all of them.
Relationships: Iwaizumi Hajime/Oikawa Tooru
Series: Meet me in the grey area [3]
Series URL: https://archiveofourown.org/series/1699420
Comments: 19
Kudos: 273





	What kind of rivalry (what kind of revelry)

**Author's Note:**

> From this prompt by [gingerly-writing](https://gingerly-writing.tumblr.com/post/157206863766/superhero-aus-13): - ‘You’re my arch nemesis but our best friends are dating…I guess I’ll play nice in civvies, for now’ AU
> 
> TW: super minor character death, it’s over fast, I promise

Long fingers ease up under the mask and within the span of a sharp inhale, Hajime is no longer the Ace, just Iwaizumi Hajime laid bare. Fingertips turn to calloused pads that trace their way down from exposed cheekbones to the corners of Hajime's lips and all he needs to do is shift, just a fraction, and he can have them on his mouth, in his mouth. 

“Iwa-chan,” The Grand King whispers and Hajime's restraint is thinning, fraying, so he tries to scowl.

“Don’t call me that,” He warns but it emerges as a gasp and in response, Oikawa’s gaze seems to soften in the penumbra. 

“Hajime, then,” He murmurs, warm lips skimming Hajime's temple, brushing over skin that’s set aflame, “ _Hajime._ ”

Hajime jerks awake with a choked gasp that startles Captain into a surprised ‘muurp’ which then settles into a disgruntled look. The phantom sensation of Oikawa's fingers, Oikawa's lips, Oikawa, have him closing his eyes, unsure of whether he's trying to erase the dream or chase it. Evidently displeased by the lack of sympathetic cuddles, Captain leaps off the bed and pads over to curl up in the little cat bed down the hallway. 

Running a hand over his face, Hajime curses The Grand King for being his enemy, for showing up at his house, for telling him his name, for looking so delicate when he’s not being an ass. Then he curses himself for dreaming about his enemy for the third night in a row. 

Sleep has grown elusive now, the blurry images replay like a broken showreel, vivid in his mind, so he forces himself through double of his usual workout until he’s drenched in sweat and more focused on the ache in his muscles than anything else. 

But the cloying, musky edges of the dream cling throughout the day, like the heavy, thick air that’s unbearably hot before rain that never comes - there’s no reprieve, there’s no relief. 

. . .

Oikawa Tooru is probably going to die. 

The heat of the explosion makes it hard to breathe and the force of it throws him, has him skidding across the gritty roof and off, over the edge. 

A breathless moment as the ground rushes towards him before his flailing hand catches on what feels like a ledge and it’s a hard jerk that has him wincing as his shoulder absorbs the intercepted momentum of his falling body. 

Twisting deftly, he swings himself into what he hopes is an empty apartment and then has to fake a smile - blabbering nonsense about the lovely carpet when it turns out _not_ to be an empty apartment - while he strides towards the door and lets himself out into a dim corridor that smells like sweat and mold. 

Tooru veers sharply into the stairwell and as his finger finds another button that initiates yet another crash a couple of buildings down, a satisfied smirk finds its way to his face amid the sweat that beads and rolls down, dripping onto the concrete staircase. 

When a large silhouette blocks the last couple of flights, a familiar tattoo barely visible under his ear, Tooru doesn’t even falter, launching himself with the railings as a springboard and vaulting over the hulking figure. 

The other man is reaching for Tooru when his neck gets snapped, and then Tooru is strolling into the bright afternoon not even checking to see if the body hits the stairs. The expression underneath his mask is flinty as he dusts off his hands and starts toward a nondescript car that sits at the end of the street. Powerful, quick and strategic - The Grand King is known to be ruthlessly efficient and invariably precise in terms of his calculations. 

Oikawa Tooru is probably going to die, but not today.

_"Leave them, your strength is wasted there, they will make you weak."_

_"You have a really warped view of the world, don't you? Don't hold your breath, I'll never get behind your twisted ideology."_

_"Then you will fall with the rest."_

Not when the underbelly of Seijoh lies in the hands of someone like _him_.

Not when the words they exchanged still burn deep in the night while Tooru reviews plan after plan, pores over blueprints and schedules, and not when this elaborate game of chess set in their city has yet to be won. 

To anyone not watching, the Grand King's attacks come at random intervals, in strange forms and with no particular target. But someone paying attention might be able to follow the intricately laid steps that Tooru is taking towards a much larger goal. 

By the time he’s reached his car, his breathing has more or less returned to normal and as he opens the door, he catches sight of someone familiar racing to the scene that he had engineered down the block. 

At once, the hard stare morphs into something different, is lit by an unusual emotion as the smirk relaxes into a somewhat more natural curve. 

“Have fun, Ace,” Tooru murmurs, slipping into the driver’s seat and listening to the engine purr to life, “Can’t have you forgetting about me, can we?” 

The drive back home is set to the latest pop hits until it’s punctuated by an incoming phone call. As he reaches for the car’s controls to accept it, his shoulder twinges again, forcing him to lean forward to hit the green icon. 

“Hi, Makki!” Tooru chirps, as though he hasn’t broken four different laws in the past hour. 

“He surprised me with a dozen profiteroles when I said I was having a bad day,” Makki moans, his lovelorn tone clear as it filters through the high grade car speakers, “I’m going to _marry_ him.”

“Isn’t this the ‘get laid and get gone’ guy?” Tooru inquires, fighting a tiny smile even though he knows Makki can’t see. 

“He was!” Makki wails, his voice filling the dark interior of the car, “But then he turned out to be my _soulmate_.” 

"So when do I get to meet this soulmate of yours?" Tooru teases as though he hasn't run full background checks on Matsukawa Issei and ascertained that his work and family pose no threat to Makki. Occupied with the statistics and information he's gleaned, he doesn't notice the way Makki pauses a little longer than necessary. 

"Soon," Makki sounds excited, and then a touch more slyly, "Soon."

. . . 

Iwaizumi knows he should have guessed his best friend was up to something the second Matsukawa sat them down at a table for four, but Matsukawa wanted him to meet his boyfriend ("Wasn't this the 'fuck around then fuck off' guy?" "He _was_.") and Iwaizumi would be damned if a stranger was going to intimidate him away from this meeting. 

"Babe!" 

Iwaizumi reins in the urge to do something possibly permanently damaging when a flurry of black jacket and pink hair bursts into his personal space to engulf his friend. Averting his gaze from the enthusiastic couple, he quickly glances up, above their heads and is met with… a very familiar pair of toffee eyes. 

Oh no, Iwaizumi thinks faintly before very forcefully, oh _no._

There's a brief split second of surprise that flits across his archenemy's face before Oikawa's lips curl into a dangerous, languid smile, eyes glittering and it knocks the breath out of Iwaizumi's lungs even as it sends a jolt of adrenaline through his veins, as though his body is already gearing up for a fight. 

Because that's what he does when he meets the Grand King they fight and then they reconvene at another date to fight some more. They don't… Play nice at Sunday brunch. 

"This is Hanamaki," Iwaizumi snaps to when Matsukawa speaks and finds himself far closer to the boyfriend in question than he expected, seeing as Hanamaki is perched on Matsukawa's lap like it's the most natural thing in the world. 

"Iwaizumi," He offers a small seated bow and Hanamaki responds in kind before waving in Oikawa's direction. 

"I managed to wrangle Oikawa from his ridiculously packed schedule," Makki twists to look at his friend from where he's seated, "Seriously, how are you so busy all the time?"

Oikawa sticks his tongue out in response and Iwaizumi feels rather blindsided by the unexpectedly childish move. 

"Hello, Mattsun, I've heard lots about you!" He trills, then he turns a coy smile onto Iwaizumi, his voice dipping into a more sultry register, "Hello, Iwa-chan."

Matsukawa, who had been amused by his own nickname, promptly bursts into laughter at this and Iwaizumi scowls, completely forgetting that he's here to make a good impression. 

"Do not call me that," He growls. 

"You were fine with it before," Oikawa pouts in a manner that's meant to be cute, eyes round and bottom lip jutting out - Iwaizumi restrains the urge to smash his fist into that face. 

"What's this?" Makki perks up with a delighted grin, "You've met before?"

"No," Iwaizumi says emphatically just as Oikawa sings a "Yes!". He levels a glare at the other man as Oikawa beams, leaning in and making a show of examining Iwaizumi's face. 

Up close, Iwaizumi can see the gold flecks in Oikawa's eyes, can smell just the faintest whiff of shampoo and cologne. He blinks and sees a version of this face that was soft in the lambent evening, a facet of his enemy he wishes he hadn't been privy to, an Oikawa that he has tried to shove into the recesses of his mind and eradicate.

"Hmm… Or I might be mistaken, the person I'm thinking of has impressive reflexes and is all strong and rugged," Oikawa taps a thoughtful finger on pink lips that are entirely too close to Iwaizumi for comfort, "And he certainly doesn't wear glasses." At that, he clinks a fingernail against the lens of Iwaizumi's glasses, his expression blazing with mirth and defiance. 

It's all Iwaizumi can do not to trap the other in a headlock and put an end to this once and for all, but Oikawa's smug face tells him he knows that Iwaizumi wouldn't do a single thing with their friends so close by. 

Clearing his throat, Iwaizumi draws back and shifts to find Hanamaki and Matsukawa rapt in their front row seats, with the most gleeful looks plastered on their conniving little faces. 

"I'll go order," He's on his feet, eager to get away, and barely waits for the others to tell him what they want before he’s headed for the counter, trying to shake the surprise and rein in his temper.

It’s when he’s waiting for their drinks that he feels the unsettling prickle at the back of his neck that has him restraining the urge to execute a quick whirl followed by a flurry of punches, instead, he turns with a stony countenance to find Oikawa well-within Iwaizumi's bounds of what one would normally consider personal space, eyes wide and sparkling as he offers a coquettish smile he’s sure is designed to bring lesser men to their knees. His frown deepens. 

“What?” Oikawa blinks, brown eyes filled with mischief as he tilts his head, resembling a puppy, “I thought you might need help with carrying all our orders.”

Iwaizumi opens his mouth to retort just as their number is called, so he sighs and collects the drink and cake laden tray, reminding himself _I’m here for Matsukawa, I’m here to be supportive. I will not deck my best friend’s potential husband’s shitty friend._

Carefully balancing so that none of the drinks spill, he starts back to their table when he sees it happen in slow motion. The way Oikawa’s eyes flash dangerously in his direction before the taller man trips on nothing and careens toward the ground; can feel it in his nerve endings the exact instant he realises that the idiot isn’t going to catch himself even though he’s seen the imbecile do goddamn acrobatics in battle. 

Amid the fury and disbelief that crowds his brain, a stretch of clarity has him reviewing his options. He could potentially let the dumbass faceplant ( _I am here to be supportive, I will not let my best friend’s potential husband’s shitty friend break his nose on our first official meeting)_. He could pass it off as an accident, no one would blame him and the Grand King would be out of commission for a couple of days at least ( _he’s seen Oikawa fight with worse than a few bruises, nothing really deters him, ~~it’s quite admirable~~ )_. 

A flash of Oikawa’s face, forehead creased with pain but struggling to get up from Hajime’s couch is what has him moving forward. 

Deftly, he steps up, transferring the tray to one hand and catching Oikawa around the waist as his arm and most of his chest takes the other man’s weight. The tray wobbles but apart from a few splashes of coffee, everything stays intact. Oikawa stares up at him, a small blush painting his otherwise pale cheeks, his mouth in a small ‘o’ as though he had expected to be in a heap on the floor by now. 

Oikawa releases the sleeve that he had grabbed hold of while the other hand, crushed between the two of them, snakes upward and winds itself around Iwaizumi’s neck. Somehow, pulling himself upright involves Oikawa shuffling further into his personal space, almost an embrace, and Iwaizumi stills as those soft lips brush his earlobe. 

“Impressive reflexes, indeed,” Oikawa breathes into the shell of Iwaizumi’s ear in a way that absolutely does _not_ electrify him. 

Abruptly, Iwaizumi spins Oikawa away, forcing him to wrench his arms upward and twirl with the motion. It’s only years of battle and the advantage of being so close that Iwaizumi notices the slight twitch in his nemesis’s face and the stiffness of one arm’s movement. He waits, frowning, for the other to be facing him before he fixes his stare on the shoulder he suspects. 

“You shouldn’t leave injuries untreated, it’s bad for you in the long run,” He says rigidly, ignoring the dumbstruck mien that settles on Oikawa, and stalks back to the table where their friends look even more delighted than before, if that were even possible. 

The time passes relatively painlessly, much to Iwaizumi’s surprise and he finds that he quite likes Hanamaki, despite his taste in friends. There are points in the conversation that he finds himself chuckling, as though he’s with old friends, and these are moments that he glances up to find intense eyes trained on him and an odd expression on Oikawa’s face. 

He means to be on his guard the entire time, but as the morning wears into afternoon, Oikawa deals out and receives a number of playful blows, whines into oblivion and exposes himself as the biggest geek Iwaizumi has ever met.

“What do you mean Alien 3 was better than Alien Resurrection?” Oikawa demands, his overly sweet drink gripped tight as Iwaizumi tries not to laugh at how strange his life has become. _I’m having brunch with my enemy and he’s debating alien movies with my best friend._

“Alien Resurrection is focused on the Ripley clone, it’s not the real deal,” Matsukawa intones, his face emotionless although Iwaizumi knows him well enough to discern the hints of a smile in his eyes. 

Oikawa gasps, and slams his glass down gently, Iwaizumi knows it’s done gently because if Oikawa had used his full strength, the glass would have shattered and the table likely would not have survived either. 

“There’s a whole mutant alien baby in Alien Resurrection!” Oikawa sputters, and Iwaizumi tries, he really does, not to follow the adorable little cowlick that bounces as Oikawa argues, brown eyes narrowed, “Resurrection has sparked an entire discourse on the notion of identity, the definition of humanity as well as inter-galactic ecology.”

Matsukawa frowns as Iwaizumi raises an eyebrow, mildly surprised by how well-substantiated Oikawa’s views seem to be. From Oikawa’s bag, an ‘I want to believe’ badge flashes in contemptuous victory.

“Fair enough,” Matsukawa relents and Oikawa laughs blithely, triumph and mirth colouring the sound. Iwaizumi hates that he notices that this is the most genuinely happy Oikawa has sounded this entire time, that even later that evening, he remembers the exact sound of that laugh, like a ringtone you hear once on the train and never forget. 

By the time they leave, the late afternoon is almost bleeding into evening and the sun has grown muted, as though waning and eager to retire, the weakened rays setting up a gentle glow that makes Oikawa look infuriatingly lovelier. Iwaizumi resolves never to have dusk battles with The Grand King lest this effect throw him off his game. 

The happy couple takes their leave first, so wrapped up in each other that they hardly wave goodbye over promises that they should do this again. There’s a brief silence after the pair round the corner and without a word, Iwaizumi pivots on his heel and begins in the direction of home. 

“Iwa-chan!” Oikawa keeps up without much effort, a grin on his face, “How rude! Aren’t you going to say goodbye? Or is it that you don’t want our time together to end just yet? If you wanted to have dinner together, you could have just as-”

Iwaizumi’s control snaps and before he can stop himself, he has Oikawa by the shirtfront, pressed against a hard brick wall in a quiet, narrow alley, tucked into the shadows. 

“Shut up,” He growls with more annoyance than actual heat. Oikawa’s pupils have dilated, his eyes darkening, gleaming as his breaths come shorter. 

“Iwa-chan,” It’s a small, fluttering sound that makes his heart contract even as his grip loosens. He knows Oikawa could easily break away, worm his way out, as he has done so often before. Instead, he stays, pinned to a wall with eyes that smoulder and lips that, in the trick of the dying light, appear to quiver with each exhale. 

“If you even consider hurting Matsukawa, I will end you,” Iwaizumi threatens, “I think we both treasure our friends enough that we can agree to keep them out of this.”

“A temporary, conditional truce,” Oikawa laughs softly and before he knows it, Iwaizumi is the one being slammed into the wall, his heart pounding as his mind screams at him for his stupidity. But as Oikawa leans in close, lips ghosting the curve of his ear, just as he did in the cafe, Iwaizumi can’t find it in himself to move. 

“Shall we seal it with a kiss then? Shaking on it is so passé.” 

Iwaizumi has no time to register this, no time to react before the lips that he’d been staring at all afternoon become a fleeting pressure on his mouth. As gentle as it is, it sears his mouth, his senses, his brain. 

“You-” He’s gathered to take a swing at Oikawa who has danced just out of reach, shrouded in the shadows, when the villain cocks his head as though listening. In the darkness, his teeth are a brilliant white. 

“It seems like you’re needed. Guess I’ll see you around, Iwa-chan,” He swears Oikawa winks as he takes three nimble steps back and blends into the darkness. Iwaizumi takes one step forward, intent on chasing when his own sharpened hearing picks up on the shrill blare of sirens almost half a city away. Setting his jaw, he casts one more searching stare into the deep dimness of the alleyway before breaking into a run in the direction of the situation. 

In the cover of the gloom, Oikawa slumps to the ground, back against the wall and one hand on his thundering heart. Repeatedly, he thumps his head on his knees, eyes squeezed shut and an unbidden smile curving. 

He’d thought that getting Iwaizumi Hajime out of his system would be easy, just a kiss and he’d stop being so curious, so unbearably hung up on the hero. But for once his calculations have failed him because that brief brush has not been a solution, had offered no reprieve, no relief. 

He brings his knuckles up to his mouth, tries to stop this line of thought before it gets more dangerous. But Iwaizumi's fond smile flashes through his mind and his lips _burn._

**Author's Note:**

> Thank you for reading! As you can see, this is part of a collection of ficlets in the same universe that started with a prompt but... Seems to have gained a life of its own based on the documents in my drive. I should be posting concurrently on [tumblr](https://redroseinsanity.tumblr.com/) as well. 
> 
> Feel free to come talk to me about haikyuu!!


End file.
